Aggregates (world)

• Aggregate is defined as a granular material used in construction, which may be natural, manufactured or re-cycled.
• Construction aggregate, or simply "aggregate", is a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone, slag, and recycled concrete.
• Aggregates are a component of composite materials such as concrete and asphalt concrete; the aggregate serves as reinforcement to add strength to the overall composite material.
• Natural Aggregates or Primary Aggregates are naturally occurring materials of rock, sand and gravel. These are extracted directly from land or marine sources for use in construction.
• Secondary Aggregates or Manufactured Aggregates are by-products of industrial processes such as steel slag or pulverised fuel ash from power stations.

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